.page-about {
  --about-rail: 208px;
  --about-flow-gap: clamp(1.4rem, 3.4vw, 2.6rem);
  --about-pad: clamp(1.1rem, 3vw, 1.6rem);
  background: var(--ink-900);
  color: var(--text);
  overflow-x: clip;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: clamp(1.5rem, 4.5vw, 3rem) 0 0;
  border-bottom: 1px solid var(--line-soft);
  background:
    radial-gradient(115% 80% at 88% 4%, rgba(108, 77, 255, 0.26), transparent 60%),
    radial-gradient(85% 70% at 2% 96%, rgba(43, 245, 212, 0.12), transparent 68%),
    linear-gradient(158deg, var(--ink-900) 0%, var(--ink-800) 55%, var(--ink-700) 100%);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  right: -8%;
  top: 6%;
  width: min(44vw, 380px);
  aspect-ratio: 1;
  background: linear-gradient(135deg, rgba(43, 245, 212, 0.18), rgba(108, 77, 255, 0) 62%);
  clip-path: polygon(0 100%, 100% 0, 100% 100%);
  opacity: 0.55;
  pointer-events: none;
}

.page-about .about-hero__inner {
  position: relative;
  display: grid;
  gap: clamp(1.4rem, 4vw, 2.4rem);
  align-items: center;
}

.page-about .about-hero__title {
  font-family: var(--font-display);
  font-size: clamp(1.95rem, 6vw, 3.6rem);
  line-height: 1.1;
  font-weight: 800;
  letter-spacing: -0.01em;
  margin: 0.7rem 0 1rem;
  max-width: 20ch;
  color: var(--text);
}

.page-about .about-hero__lead {
  margin: 0 0 1.4rem;
  max-width: 46ch;
  font-size: clamp(0.95rem, 1.6vw, 1.06rem);
  line-height: 1.85;
  color: rgba(230, 241, 255, 0.82);
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.7rem;
}

.page-about .about-hero__figure {
  margin: 0;
  line-height: 0;
  border: 1px solid var(--line);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 26px), calc(100% - 26px) 100%, 0 100%);
  box-shadow: 0 0 0 1px rgba(5, 11, 24, 0.6);
}

.page-about .about-hero__figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
}

.page-about .about-stats {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: clamp(1.6rem, 4vw, 2.6rem) 0 0;
  padding: 0;
  background: rgba(138, 164, 200, 0.16);
  border-top: 1px solid rgba(138, 164, 200, 0.16);
}

.page-about .about-stats li {
  display: flex;
  flex-direction: column;
  gap: 0.3rem;
  padding: 0.9rem clamp(0.75rem, 2vw, 1.25rem);
  background: var(--ink-800);
}

.page-about .about-stats__num {
  font-family: var(--font-mono);
  font-size: clamp(1.3rem, 3.6vw, 1.85rem);
  font-weight: 700;
  line-height: 1;
  color: var(--text);
}

.page-about .about-stats__num em {
  font-style: normal;
  font-size: 0.6em;
  margin-left: 0.18em;
  color: var(--cyan);
}

.page-about .about-stats__label {
  font-size: 0.79rem;
  line-height: 1.5;
  letter-spacing: 0.02em;
  color: var(--mist);
}

/* ---------- 主体：索引 + 连续画布 ---------- */
.page-about .about-body {
  display: grid;
  gap: var(--about-flow-gap);
  padding-block: clamp(1.8rem, 5vw, 3.4rem) clamp(0.6rem, 2vw, 1rem);
}

.page-about .about-index {
  border-top: 1px solid var(--line);
  padding-top: 0.85rem;
  min-width: 0;
}

.page-about .about-index__title {
  margin: 0 0 0.7rem;
  font-size: 0.7rem;
  letter-spacing: 0.24em;
  color: var(--mist);
}

.page-about .about-index__list {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin: 0;
  padding: 0;
}

.page-about .about-index__link {
  display: flex;
  align-items: baseline;
  gap: 0.55rem;
  padding: 0.42rem 0.62rem;
  font-size: 0.86rem;
  line-height: 1.4;
  color: var(--mist);
  text-decoration: none;
  border: 1px solid var(--line-soft);
  background: rgba(11, 31, 58, 0.55);
  transition: color 0.2s var(--ease), border-color 0.2s var(--ease), background 0.2s var(--ease);
}

.page-about .about-index__num {
  font-size: 0.72rem;
  color: var(--gold);
}

.page-about .about-index__link:hover,
.page-about .about-index__link:focus-visible {
  color: var(--text);
  border-color: var(--cyan);
  background: rgba(43, 245, 212, 0.08);
}

.page-about .about-flow {
  display: grid;
  gap: clamp(1.7rem, 4vw, 2.8rem);
  min-width: 0;
}

.page-about .about-block {
  position: relative;
  padding-bottom: clamp(1.4rem, 3.6vw, 2.2rem);
  border-bottom: 1px solid var(--line-soft);
  min-width: 0;
}

.page-about .about-block:last-child {
  border-bottom: 0;
}

.page-about .about-coord {
  margin: 0 0 0.55rem;
  font-size: 0.72rem;
  letter-spacing: 0.2em;
  color: var(--cyan);
}

.page-about .about-coord::before {
  content: "";
  display: inline-block;
  width: 24px;
  height: 1px;
  margin-right: 0.6rem;
  vertical-align: middle;
  background: var(--cyan);
  box-shadow: 0 0 9px rgba(43, 245, 212, 0.7);
}

.page-about .about-block__title {
  font-family: var(--font-display);
  font-size: clamp(1.35rem, 3.4vw, 2rem);
  line-height: 1.25;
  font-weight: 700;
  margin: 0 0 0.95rem;
  color: var(--text);
  max-width: 24ch;
}

.page-about .about-text {
  margin: 0 0 1rem;
  max-width: 62ch;
  font-size: 1rem;
  line-height: 1.85;
  color: rgba(230, 241, 255, 0.84);
}

.page-about .about-text a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(43, 245, 212, 0.4);
}

.page-about .about-inline-link {
  margin: 1.1rem 0 0;
}

.page-about .about-inline-link a {
  display: inline-block;
  font-size: 0.9rem;
  color: var(--gold);
  text-decoration: none;
  padding-bottom: 2px;
  border-bottom: 1px solid var(--line-gold);
  transition: color 0.2s var(--ease), border-color 0.2s var(--ease);
}

.page-about .about-inline-link a:hover,
.page-about .about-inline-link a:focus-visible {
  color: var(--text);
  border-color: var(--cyan);
}

.page-about .about-figure {
  margin: 1.3rem 0 0;
  line-height: 0;
  border: 1px solid var(--line-soft);
  clip-path: polygon(0 0, calc(100% - 20px) 0, 100% 20px, 100% 100%, 0 100%);
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
}

/* ---------- 会员中心时间轴 ---------- */
.page-about .about-track {
  list-style: none;
  margin: 1.2rem 0 0;
  padding: 0 0 0 1.45rem;
  position: relative;
}

.page-about .about-track::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.5rem;
  bottom: 0.6rem;
  width: 1px;
  background: linear-gradient(180deg, var(--cyan), rgba(108, 77, 255, 0.7) 62%, rgba(138, 164, 200, 0) 100%);
}

.page-about .about-track__item {
  position: relative;
  padding-bottom: 1.35rem;
}

.page-about .about-track__item:last-child {
  padding-bottom: 0;
}

.page-about .about-track__item::before {
  content: "";
  position: absolute;
  left: -1.79rem;
  top: 0.42rem;
  width: 0.62rem;
  height: 0.62rem;
  background: var(--ink-900);
  border: 1px solid var(--cyan);
  transform: rotate(45deg);
}

.page-about .about-track__step {
  display: block;
  margin-bottom: 0.22rem;
  font-family: var(--font-mono);
  font-size: 0.73rem;
  letter-spacing: 0.16em;
  color: var(--gold);
}

.page-about .about-track__title {
  margin: 0 0 0.3rem;
  font-size: 1.02rem;
  line-height: 1.45;
  font-weight: 700;
  color: var(--text);
}

.page-about .about-track__desc {
  margin: 0;
  max-width: 60ch;
  font-size: 0.94rem;
  line-height: 1.8;
  color: rgba(230, 241, 255, 0.76);
}

/* ---------- 服务原则 ---------- */
.page-about .about-rules {
  list-style: none;
  display: grid;
  gap: 1px;
  margin: 1.2rem 0 1.2rem;
  padding: 0;
  background: var(--line-soft);
  border: 1px solid var(--line-soft);
}

.page-about .about-rule {
  background: var(--ink-800);
  padding: var(--about-pad);
  min-width: 0;
}

.page-about .about-rule__num {
  display: block;
  margin-bottom: 0.45rem;
  font-size: 0.72rem;
  letter-spacing: 0.18em;
  color: var(--cyan);
}

.page-about .about-rule__title {
  margin: 0 0 0.4rem;
  font-size: 1rem;
  font-weight: 700;
  color: var(--text);
}

.page-about .about-rule__desc {
  margin: 0;
  font-size: 0.9rem;
  line-height: 1.78;
  color: rgba(230, 241, 255, 0.76);
}

/* ---------- 收尾：长期运营 ---------- */
.page-about .about-close {
  margin-top: clamp(1.6rem, 4vw, 2.6rem);
  padding-top: clamp(1.8rem, 5vw, 3rem);
  border-top: 1px solid var(--line);
  background:
    radial-gradient(90% 70% at 50% 0%, rgba(108, 77, 255, 0.2), transparent 62%),
    linear-gradient(180deg, var(--ink-800), var(--ink-900));
  overflow: hidden;
}

.page-about .about-metrics {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1rem;
  margin: 1.3rem 0 0;
  padding: 0;
}

.page-about .about-metric {
  display: grid;
  grid-template-columns: auto auto;
  justify-content: start;
  align-items: baseline;
  gap: 0 0.2rem;
  padding-top: 0.8rem;
  border-top: 2px solid var(--line-gold);
  min-width: 0;
}

.page-about .about-metric:nth-child(2) {
  border-top-color: rgba(43, 245, 212, 0.6);
}

.page-about .about-metric:nth-child(3) {
  border-top-color: rgba(108, 77, 255, 0.75);
}

.page-about .about-metric:nth-child(4) {
  border-top-color: rgba(138, 164, 200, 0.5);
}

.page-about .about-metric__num {
  font-size: clamp(1.45rem, 4vw, 2.05rem);
  font-weight: 700;
  line-height: 1;
  color: var(--gold);
}

.page-about .about-metric__unit {
  font-size: 0.82rem;
  color: var(--mist);
}

.page-about .about-metric__label {
  grid-column: 1 / -1;
  margin-top: 0.45rem;
  font-size: 0.8rem;
  line-height: 1.5;
  color: rgba(230, 241, 255, 0.72);
}

.page-about .about-close__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.7rem;
  margin-top: 1.6rem;
}

.page-about .about-close__figure {
  margin: clamp(1.5rem, 4vw, 2.4rem) 0 0;
  line-height: 0;
  mask-image: linear-gradient(180deg, rgba(5, 11, 24, 0.95), rgba(5, 11, 24, 0.45));
  -webkit-mask-image: linear-gradient(180deg, rgba(5, 11, 24, 0.95), rgba(5, 11, 24, 0.45));
}

.page-about .about-close__figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
}

/* ---------- 响应式 ---------- */
@media (min-width: 720px) {
  .page-about .about-rules {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-about .about-metrics {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (min-width: 760px) {
  .page-about .about-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (min-width: 900px) {
  .page-about .about-hero__inner {
    grid-template-columns: minmax(0, 1.06fr) minmax(0, 0.94fr);
    align-items: end;
  }

  .page-about .about-hero__figure {
    transform: translateY(0.4rem);
  }
}

@media (min-width: 940px) {
  .page-about .about-body {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    gap: clamp(2rem, 4.5vw, 3.6rem);
    align-items: start;
  }

  .page-about .about-index {
    position: sticky;
    top: calc(var(--header-h) + 1.2rem);
  }

  .page-about .about-index__list {
    flex-direction: column;
    flex-wrap: nowrap;
    gap: 0;
  }

  .page-about .about-index__link {
    border: 0;
    border-left: 1px solid transparent;
    background: none;
    padding: 0.46rem 0.5rem;
  }

  .page-about .about-index__link:hover,
  .page-about .about-index__link:focus-visible {
    border-left-color: var(--cyan);
  }
}

@media (min-width: 1180px) {
  .page-about {
    --about-rail: 232px;
  }

  .page-about .about-hero__lead {
    font-size: 1.08rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-index__link,
  .page-about .about-inline-link a {
    transition: none;
  }

  .page-about .about-hero__figure {
    transform: none;
  }
}